The goal of this research is to develop surface enhanced Raman scattering (SERS) and surface enhanced resonance Raman scattering (SERRS) techniques for the study of biomolecules. During this funding period there are four specific aims. The first is to continue the development of new substrates for SERS/SERRS. This will include the use of Au and Cu as well as Ag in the form of electrodes, thin films, and coated spheres of known size distribution. The application of SERS to the study of chemically modified surfaces (especially SnO2 and carbon) will also be continued. Modification will be accomplished by spontaneous adsorption, deposition of Langmuir Blodgett monolayers, and covalent bonding. The second aim is to pursue SERS investigations of amino acids, proteins, and lipids on the above named metals, as well as the modified electrode surfaces. The objective is to identify specific interactions between these molecules and the electrode surfaces. The application of SERRS to mechanistic studies of electron transfer proteins constitutes the third aim. Methods for the evaluation of activity and structure in flavoenzymes and cytochrome c will be sought. New procedures for adsorbing these proteins to electrode surfaces will be attempted in an effort to preserve their native structure. A number of proteins containing chromosphores will also be examined by SERRS. These will include photosynthetic preparations, phytochrome, and phycocyanin. The goal of these studies is to utilize the surface sensitivity of SERRS to determine structural information about the proteins. The fourth aim is to pursue purely analytical applications of SERS/SERRS. This will include detection of proteins separated by chromatography. Methods for detecting the interaction of small chromophoric molecules with capture proteins will also be investigated. In all of the above studies, an effort will be made to increase the sensitivity of the surface Raman technique through the use of new experimental approaches (i.e. fiber optics, attenuated total reflectance and micro Raman sampling procedures). Advances in detector technology will also be important with respect to this goal.